As was foretold by Linus in It's the Great Blumpkin Charlie Brown! It is the king of all blumpkins and can only be had on Halloween night. According to Norse folklore, it is the best blowjob that you can possibly get while sitting on a toilet and taking a shit.

Rick: Yo, Sal, it was halloween last night, did the Great Blumpkin show up?
Sal: Yeah, i had like three calzones and then I wanted to take a shit but she wanted to get kinky. Let's just say The Great Blumpkin arrived on schedule
Rick: Sick
Sal: Ya, totally fuckin sick